Is peficitinib an effective treatment for rheumatoid arthritis?

This study looked at the use of peficitinib (Smyraf) for the treatment of rheumatoid arthritis (RA) from the perspective of patients and their doctors. It found that peficitinib improved symptoms of RA and led to increased ability to work and carry out daily activities compared to placebo.

RA is a chronic inflammatory disease. It is associated with pain and disability and reduced quality of life. There are many medications available for RA. These are called disease-modifying anti-rheumatic drugs (DMARDs). Their effectiveness is commonly measured through certain objective factors such as inflammatory markers in the blood. However, how patients report the severity of their symptoms is important. This is referred to as patient-reported outcomes (PROs).

Peficitinib is a new treatment for RA. It acts on the immune system to reduce inflammation. It has been shown to be safe and effective in patients with RA. However, the PROs for this medication are still unknown.

1,025 patients with RA participated in this study. Patients were divided into 3 groups. Group 1 received peficitinib 100 mg daily, group 2 received peficitinib 150 mg daily and group 3 received a placebo. The PROs were evaluated using questionnaires after 4, 8, and 12 weeks of treatment. One of these questionnaires was the Work Productivity and Activity Impairment (WPAI) questionnaire. The WPAI questionnaire asks patients to estimate how much work they have missed due to illness, how much their productivity has been affected and how much their daily activities have been affected. Lower scores indicate better disease control.

After 12 weeks, patients treated with peficitinib had significantly reduced scores across all sections of the WPAI questionnaire compared to the placebo group. After 12 weeks scores for "loss of productivity" changed from baseline by -12.2 in group 1, by -18.68 in group 2, and by +3.62 points in group 3. Scores for "daily activity impairment" changed from baseline by -19.61 in group 1, by -24.65 in group 2, and by -4.65 points in group 3.

This study showed that treatment with peficitinib 100 mg or 150 mg daily improved PROs in patients with RA. 

This study was based in Asia. Further studies are needed to determine if these findings apply to other ethnicities as well. This study was funded by Astellas Pharma Inc, the manufacturer of peficitinib.